L_DespeckleBitmap (original) (raw)

Summary

Removes speckles from a bitmap. Typically, this function is used to clean up scanned images (such as FAX images).

Syntax

#include "l_bitmap.h"

L_LTIMGCOR_API L_INT L_DespeckleBitmap(pBitmap, uFlags)

Parameters

pBITMAPHANDLE pBitmap

Pointer to the bitmap handle that references the bitmap to be affected.

L_UINT32 uFlags

Reserved for future use. Must be 0.

Returns

Comments

This function does not support signed data images. It returns the error code ERROR_SIGNED_DATA_NOT_SUPPORTED if a signed data image is passed to this function.

This function removes 1-pixel speckles, and shrinks some larger speckles. Therefore, in some cases, larger speckles can be completely removed by running it more than once.

To update a status bar or detect a user interrupt during execution of this function, refer to L_SetStatusCallback.

This function supports 12 and 16-bit grayscale and 48 and 64-bit color images. Support for 12 and 16-bit grayscale and 48 and 64-bit color images is available in the Document and Medical Imaging toolkits.

This function does not support 32-bit grayscale images. It returns the error code ERROR_GRAY32_UNSUPPORTED if a 32-bit grayscale image is passed to this function.

Despeckle Function - Before

Despeckle Function - After

View additional platform support for this Despeckle function.

Required DLLs and Libraries

• LTIMGCOR
• For a listing of the exact DLLs and Libraries needed, based on the toolkit version, refer to Files To Be Included With Your Application.

Platforms

Win32, x64, Linux.

See Also

Functions

• L_DeskewBitmap
• L_WindowLevel
• L_BricksTextureBitmap
• L_DeskewBitmap
• L_DiffuseGlowBitmap
• L_GlowFilterBitmap
• L_HalfTonePatternBitmap
• L_HighPassFilterBitmap
• L_MaskConvolutionBitmap
• L_PerspectiveBitmap
• L_PlasmaFilterBitmap
• L_PointillistBitmap
• L_FragmentBitmap
• L_HighPassFilterBitmap
• L_UnsharpMaskBitmap
• L_BlankPageDetectorBitmap
• L_AutoBinarizeBitmap
• L_DynamicBinaryBitmap
• L_AutoBinaryBitmap
• L_AutoZoneBitmap
• L_InvertedPageBitmap

Topics

• Raster Image Functions: Doing Geometric Transformations
• Raster Image Functions: Filtering Images
• Removing Noise

Example

For complete sample code, refer to the CHILD.C module of the DEMO example.
This example loads a bitmap and removes speckles from it.

L_INT DespeckleBitmapExample(L_VOID) { L_INT nRet; BITMAPHANDLE LeadBitmap; /* Bitmap handle to hold the loaded image. */ /* Load the bitmap, keeping the bits per pixel of the file */ nRet = L_LoadBitmap(MAKE_IMAGE_PATH(TEXT("IMAGE1.CMP")), &LeadBitmap, sizeof(BITMAPHANDLE), 0, ORDER_BGR, NULL, NULL); if (nRet != SUCCESS) return nRet; /* Remove speckles from the bitmap */ nRet = L_DespeckleBitmap(&LeadBitmap, 0); if (nRet != SUCCESS) return nRet; nRet = L_SaveBitmap(MAKE_IMAGE_PATH(TEXT("Result.BMP")), &LeadBitmap, FILE_BMP, 24, 0, NULL); if (nRet != SUCCESS) return nRet; //free bitmap if (LeadBitmap.Flags.Allocated) L_FreeBitmap(&LeadBitmap); return SUCCESS; }